3– Imam Ali (AS) when asked about who has the greatest misfortune, said, ‘A man who abandons the world for the sake of the world, and therefore he misses out on the world and loses the Hereafter, and a man who worships, struggles and fasts as a display for others, and thus forbids
[himself] the pleasures of this world and also tires himself. And were he to do all that sincerely
[for the sake of Allah], he would be deserving of its reward.’
[Tanbih al-Khawatir, v. 2, p. 95]

4– Imam Ali (AS) said, ‘Verily the biggest loser with the worst end of the deal and the most unsuccessful in his striving is the man who exerts himself in the quest for his wealth even though fate does not help him in his aims, and he consequently leaves this world with regret while heading towards the Hereafter, where he will face its ill consequences.’
[Nahj al-Balagha, Saying 430]